/* Metronomad — project styles.
   Design tokens: ../src/css/variables.css
   Base button/input styles: root Style.css
*/

#app {
    max-width: 640px;
    margin: 0 auto;
    padding-top: var(--space-2);
}

/* Header */
.app-header {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-bottom: var(--space-4);
}

.app-title {
    margin: 0;
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--color-primary);
}

.home-link {
    color: var(--color-text-secondary);
    text-decoration: none;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-1);
    border-radius: var(--radius-small);
    min-width: 44px;
    min-height: 44px;
    transition: color var(--transition-fast), background-color var(--transition-fast);
}

.home-link:hover {
    color: var(--color-primary);
    background-color: var(--color-surface-variant);
}

.home-link:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

.home-icon {
    font-size: 18px;
}

/* Theme toggle (shared ../src/js/themeSwitcher.js) */
#themeToggle {
    position: fixed;
    top: var(--space-3);
    right: var(--space-3);
    z-index: 100;
    background-color: var(--color-surface);
    border: none;
    border-radius: 50%;
    box-shadow: var(--elevation-1);
}

/* Buttons (purecss is not loaded in this project — self-contained) */
.mn-btn {
    background-color: var(--color-surface-variant);
    color: var(--color-text-primary);
    border: none;
    min-height: 44px;
}

.mn-btn:hover:not(:disabled) {
    box-shadow: var(--elevation-1);
}

.mn-btn--primary {
    background-color: var(--color-primary);
    color: var(--color-on-primary);
}

.mn-btn--primary:hover:not(:disabled) {
    background-color: var(--color-primary-hover);
}

.mn-btn--primary:active:not(:disabled) {
    background-color: var(--color-primary-pressed);
}

.mn-btn .material-icons {
    font-size: 18px;
    margin-right: var(--space-1);
    vertical-align: middle;
}

/* Drop zone */
.drop-zone {
    border: 2px dashed var(--color-surface-variant);
    border-radius: var(--radius-large);
    background-color: var(--color-surface);
    padding: var(--space-6);
    text-align: center;
    transition: border-color var(--transition-fast), background-color var(--transition-fast);
}

.drop-zone--hero {
    min-height: 40vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--space-4);
}

.drop-zone--dragover {
    border-color: var(--color-primary);
    background-color: var(--color-surface-variant);
}

.drop-zone-status {
    margin: 0 0 var(--space-2);
    color: var(--color-text-secondary);
    font-size: var(--font-size-base);
}

.file-input-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* File row (KB-2: ellipsis + title tooltip) */
.file-row {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    background-color: var(--color-surface);
    border-radius: var(--radius-medium);
    box-shadow: var(--elevation-1);
    padding: var(--space-2) var(--space-4);
    margin: var(--space-4) 0;
}

.file-icon {
    color: var(--color-primary);
    flex-shrink: 0;
}

.file-name {
    flex: 1 1 auto;
    min-width: 0; /* allows ellipsis inside flex */
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-duration {
    flex-shrink: 0;
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    font-variant-numeric: tabular-nums;
}

/* Parameter controls */
.controls {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4) var(--space-6);
    background-color: var(--color-surface);
    border-radius: var(--radius-medium);
    box-shadow: var(--elevation-1);
    padding: var(--space-4);
    transition: opacity var(--transition-fast);
}

.controls--locked {
    opacity: 0.7;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
}

.control-group label {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    margin: 0;
}

.control-group--offset {
    flex: 1 1 200px;
}

.control-group--offset input[type="range"] {
    width: 100%;
}

.bpm-stepper {
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

.bpm-stepper input[type="number"] {
    width: 80px;
    text-align: center;
}

.stepper-btn {
    min-width: 44px;
    padding-left: 0;
    padding-right: 0;
    font-size: var(--font-size-lg);
    line-height: 1;
}

.clamp-hint {
    margin: 0;
    font-size: var(--font-size-xs);
    color: var(--color-accent);
}

/* Playback buttons */
.playback-controls {
    display: flex;
    gap: var(--space-3);
    justify-content: center;
    margin: var(--space-5) 0;
}

/* Beat dots — the active/pulse/static classes are set imperatively by
   createBeatDots (Phase 6); --beat-interval is set on the row per tempo, so
   the pulse runs at the song's beat rate. */
.beat-dots {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--space-3);
    margin: var(--space-4) 0;
}

.beat-dot {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background-color: var(--color-surface-variant);
    transition: background-color var(--transition-fast);
}

.beat-dot--downbeat {
    width: 20px;
    height: 20px;
}

.beat-dot--active {
    background-color: var(--color-primary);
}

/* Pulse variant (default motion preference) — one scale pulse per beat. */
.beat-dot--active.beat-dot--pulse {
    animation: beat-pulse var(--beat-interval, 0.5s) ease-out;
}

/* Static variant (B-03: JS honors prefers-reduced-motion; the media query
   below is the no-JS / safety net, U-22). */
.beat-dot--active.beat-dot--static {
    animation: none;
}

@keyframes beat-pulse {
    0% { transform: scale(1.35); }
    100% { transform: scale(1); }
}

@media (prefers-reduced-motion: reduce) {
    .beat-dot--active,
    .beat-dot--static {
        animation: none;
    }
}

/* Waveform progress (CR 2026-08-23-001 Phase 4 — replaces the 8px bar).
   The old 8px fill rule is deleted: its only consumer (the template's
   fill div) was removed; the progressPercent computed survives (R-4).
   .progress-track / .progress-offset-marker remain as the O-2 placeholder
   shown until the peaks are painted. */
.progress {
    margin: var(--space-4) 0;
}

.progress-track {
    position: relative;
    height: 8px;
    background-color: var(--color-surface-variant);
    border-radius: 4px;
}

.progress-offset-marker {
    position: absolute;
    top: -3px;
    width: 2px;
    height: 14px;
    background-color: var(--color-accent);
}

/* The waveform container. pan-y, not none: horizontal scrub → JS (Phase 5),
   vertical swipe still scrolls (W-2, skill interaction.md). */
.waveform {
    position: relative;
    height: 64px;
    touch-action: pan-y;
}

/* W-4: the file's first width breakpoint — narrow phones get 48 px
   (pinned by E2E-3.4). */
@media (max-width: 375px) {
    .waveform {
        height: 48px;
    }
}

#waveformCanvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    display: block;
    cursor: crosshair;
}

/* Param lock (U-12 CSS line; the isParamLocked JS guard is the backstop):
   a canvas can never be :disabled (R-1) — pointer-events is the lock. */
.waveform--locked #waveformCanvas {
    pointer-events: none;
}

/* Overlays: all pointer-events:none — the canvas (Phase 5 slider) and the
   placeholder track stay the only interactive surfaces. The KB-6 hooks
   (data-loaded, data-position-tenths) carry NO styling (do not style them). */
.waveform-offset-marker {
    position: absolute;
    top: 0;
    width: 2px;
    height: 100%;
    background-color: var(--color-accent);
    pointer-events: none;
}

/* The playhead: a DOM overlay, not a canvas repaint (PERF-2) — it moves in
   the existing 10 Hz tenths steps and STAYS under prefers-reduced-motion
   (KB-14: functional position indicator, no CSS animation). */
.waveform-playhead {
    position: absolute;
    top: 0;
    width: 2px;
    height: 100%;
    background-color: var(--color-primary);
    pointer-events: none;
}

/* O-4: one cheap pre-offset dim overlay. */
.waveform-dim {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.25);
    pointer-events: none;
}

.progress-readout {
    margin-top: var(--space-1);
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    font-variant-numeric: tabular-nums;
    text-align: right;
}

/* Error banner (D8: non-blocking overlay) */
.error-banner {
    margin-top: var(--space-4);
    padding: var(--space-3) var(--space-4);
    background-color: var(--color-surface-variant);
    color: var(--color-error);
    border-left: 4px solid var(--color-error);
    border-radius: var(--radius-small);
}

/* Screen-reader-only live region */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}